RENO, Nev. (AP) — A swarm of nearly 100 small earthquakes has been shaking the ground in northern Nevada but experts say they’ve been so tiny most people didn’t even notice.

The University of Nevada, Reno’s Seismological Laboratory say more than 90 events were confirmed on the south edge of town between 10:30 p.m. Thursday and 11 a.m. Friday in an area where the Mount Rose Highway intersects with U.S. Interstate 580.

The largest was a magnitude 2.6.

There have been no reports of damage and fewer than 40 people have reported feeling them on the lab’s web site.

Ken Smith, the lab’s associate director, says they are monitoring the situation closely and updating local emergency management officials in case the sequence evolves to a larger, damaging earthquake.